Prior Art
The invention relates to a chain amplifier including one or more amplifier stages, wherein each stage contains several field-effect transistors which are connected in such a way that all source terminals are at a given common potential, all gate terminals are connected together by means of series-connected ohmic resistors and inductances to form a gate line, and capacities or capacitances are disposed parallel to the gate line in such a manner that the leads of the capacitances which are not connected to the gate line are at the same respective source potential, all of the drain terminals are connected together by means of series-connected inductances to form a drain line, the drain line is connected on one hand, by means of ohmic resistors connected parallel to the drain line, to the common source potential, and on the other hand, the drain line is connected by means of capacitances, connected parallel to the drain line, to the common source potential, and capacitances, inductances and ohmic resistors are provided as matching elements at the input, output and at transitions from one stage to the next.
Such a single-stage chain amplifier is known in principle from the publication "International elektronische Rundschau", Vol 21, 1967, No. 5, Pages 109 to 115. The components required for the chain amplifier such as capacities or capacitances and inductances, however, are discrete components which are connected together with the transistors contained in the semiconductor chip, to form a chain amplifier. Furthermore, connecting discrete external components in an amplifier circuit is not sufficient in order to obtain amplifiers with extreme band width. If such amplifier circuits are to operate with output powers of 0.1 watt to 1 watt over a frequency range as wide as possible up to 18 GHz, the self-inductances, self-capacities and the inherent resistances of the connected field-effect transistors must also be taken into consideration.